Gay's Cinco De Mayo. The Morgan Horse Magazine, July 1971

He had an excellent pedigree. 

https://www.allbreedpedigree.com/gays+cinco+de+mayo

His sire was the very good, Moro Hill Gay Ethan, Full Lippitt, and a proven sire in his own right. Gay Ethan's sire, Dyberry Ethan, was also a proven sire, and the sire line continues on back with proven sires. 

Cinco's dam was from good California breeding that went back to Richard Sellman of Texas, Roland Hill of California, W P Thornhill of Texas, Elmer Brown of Kansas, and some good Old Midwest lines (Anndy Pershing). 

He was the sire of many in Canada--

https://www.allbreedpedigree.com/index.php?h=gays+cinco+de+mayo&g=5&query_type=progeny&search_bar=progeny&done=y&inbred=Standard&x2=n&username=&password=&x=0&y=0

and his descendants can be found today.

I like his conformation and breed type.